ethdev: change vtune profiling approach

ethdev: change vtune profiling approach

The patch changes rx_burst profiling approach:
	1. VTune's instrumentation is removed
	2. empty hook callback for profiling is added
This way all VTune-specific logic moves to the VTune side.
Hook is enabled only when CONFIG_RTE_ETHDEV_PROFILE_WITH_VTUNE option
is turned on. VTune uses this hook to attach to the polling cycle. It
is not possible to attach to the rx_burst directly, as it is inline.

Signed-off-by: Ilia Kurakin <ilia.kurakin@intel.com>
Acked-by: Keith Wiles <keith.wiles@intel.com>
Acked-by: Ferruh Yigit <ferruh.yigit@intel.com>